AWS SDK Version 3 for .NET
API Reference

AWS services or capabilities described in AWS Documentation may vary by region/location. Click Getting Started with Amazon AWS to see specific differences applicable to the China (Beijing) Region.

Uploads a part in a multipart upload.

In this operation, you provide new data as a part of an object in your request. However, you have an option to specify your existing Amazon S3 object as a data source for the part you are uploading. To upload a part from an existing object, you use the UploadPartCopy operation.

You must initiate a multipart upload (see CreateMultipartUpload) before you can upload any part. In response to your initiate request, Amazon S3 returns an upload ID, a unique identifier that you must include in your upload part request.

Part numbers can be any number from 1 to 10,000, inclusive. A part number uniquely identifies a part and also defines its position within the object being created. If you upload a new part using the same part number that was used with a previous part, the previously uploaded part is overwritten.

For information about maximum and minimum part sizes and other multipart upload specifications, see Multipart upload limits in the Amazon S3 User Guide.

After you initiate multipart upload and upload one or more parts, you must either complete or abort multipart upload in order to stop getting charged for storage of the uploaded parts. Only after you either complete or abort multipart upload, Amazon S3 frees up the parts storage and stops charging you for the parts storage.

For more information on multipart uploads, go to Multipart Upload Overview in the Amazon S3 User Guide .

Directory buckets - For directory buckets, you must make requests for this API operation to the Zonal endpoint. These endpoints support virtual-hosted-style requests in the format https://bucket_name.s3express-az_id.region.amazonaws.com/key-name. Path-style requests are not supported. For more information, see Regional and Zonal endpoints in the Amazon S3 User Guide.

Permissions
  • General purpose bucket permissions - For information on the permissions required to use the multipart upload API, see Multipart Upload and Permissions in the Amazon S3 User Guide.

  • Directory bucket permissions - To grant access to this API operation on a directory bucket, we recommend that you use the CreateSession API operation for session-based authorization. Specifically, you grant the s3express:CreateSession permission to the directory bucket in a bucket policy or an IAM identity-based policy. Then, you make the CreateSession API call on the bucket to obtain a session token. With the session token in your request header, you can make API requests to this operation. After the session token expires, you make another CreateSession API call to generate a new session token for use. Amazon Web Services CLI or SDKs create session and refresh the session token automatically to avoid service interruptions when a session expires. For more information about authorization, see CreateSession.

Data integrity

General purpose bucket - To ensure that data is not corrupted traversing the network, specify the Content-MD5 header in the upload part request. Amazon S3 checks the part data against the provided MD5 value. If they do not match, Amazon S3 returns an error. If the upload request is signed with Signature Version 4, then Amazon Web Services S3 uses the x-amz-content-sha256 header as a checksum instead of Content-MD5. For more information see Authenticating Requests: Using the Authorization Header (Amazon Web Services Signature Version 4).

Directory buckets - MD5 is not supported by directory buckets. You can use checksum algorithms to check object integrity.

Encryption
  • General purpose bucket - Server-side encryption is for data encryption at rest. Amazon S3 encrypts your data as it writes it to disks in its data centers and decrypts it when you access it. You have mutually exclusive options to protect data using server-side encryption in Amazon S3, depending on how you choose to manage the encryption keys. Specifically, the encryption key options are Amazon S3 managed keys (SSE-S3), Amazon Web Services KMS keys (SSE-KMS), and Customer-Provided Keys (SSE-C). Amazon S3 encrypts data with server-side encryption using Amazon S3 managed keys (SSE-S3) by default. You can optionally tell Amazon S3 to encrypt data at rest using server-side encryption with other key options. The option you use depends on whether you want to use KMS keys (SSE-KMS) or provide your own encryption key (SSE-C).

    Server-side encryption is supported by the S3 Multipart Upload operations. Unless you are using a customer-provided encryption key (SSE-C), you don't need to specify the encryption parameters in each UploadPart request. Instead, you only need to specify the server-side encryption parameters in the initial Initiate Multipart request. For more information, see CreateMultipartUpload.

    If you request server-side encryption using a customer-provided encryption key (SSE-C) in your initiate multipart upload request, you must provide identical encryption information in each part upload using the following request headers.

    • x-amz-server-side-encryption-customer-algorithm

    • x-amz-server-side-encryption-customer-key

    • x-amz-server-side-encryption-customer-key-MD5

  • Directory bucket - For directory buckets, only server-side encryption with Amazon S3 managed keys (SSE-S3) (AES256) is supported.

For more information, see Using Server-Side Encryption in the Amazon S3 User Guide.

Special errors
  • Error Code: NoSuchUpload

    • Description: The specified multipart upload does not exist. The upload ID might be invalid, or the multipart upload might have been aborted or completed.

    • HTTP Status Code: 404 Not Found

    • SOAP Fault Code Prefix: Client

HTTP Host header syntax

Directory buckets - The HTTP Host header syntax is Bucket_name.s3express-az_id.region.amazonaws.com.

The following operations are related to UploadPart:

Note:

For .NET Core this operation is only available in asynchronous form. Please refer to UploadPartAsync.

Namespace: Amazon.S3
Assembly: AWSSDK.S3.dll
Version: 3.x.y.z

Syntax

C#
public virtual UploadPartResponse UploadPart(
         UploadPartRequest request
)

Parameters

request
Type: Amazon.S3.Model.UploadPartRequest

Container for the necessary parameters to execute the UploadPart service method.

Return Value


The response from the UploadPart service method, as returned by S3.

Examples

This example shows how to upload 13MB of data using mutlipart upload.
The data is contained in a stream and the upload is done in 3 parts: 5MB, 5MB, then the remainder.

Multipart Upload Sample


int MB = (int)Math.Pow(2, 20);

// Create a client
AmazonS3Client client = new AmazonS3Client();

// Define input stream
Stream inputStream = Create13MBDataStream();

// Initiate multipart upload
InitiateMultipartUploadRequest initRequest = new InitiateMultipartUploadRequest
{
    BucketName = "SampleBucket",
    Key = "Item1"
};
InitiateMultipartUploadResponse initResponse = client.InitiateMultipartUpload(initRequest);

// Upload part 1
UploadPartRequest uploadRequest = new UploadPartRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId,
    PartNumber = 1,
    PartSize = 5 * MB,
    InputStream = inputStream
};
UploadPartResponse up1Response = client.UploadPart(uploadRequest);

// Upload part 2
uploadRequest = new UploadPartRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId,
    PartNumber = 2,
    PartSize = 5 * MB,
    InputStream = inputStream
};
UploadPartResponse up2Response = client.UploadPart(uploadRequest);

// Upload part 3
uploadRequest = new UploadPartRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId,
    PartNumber = 3,
    InputStream = inputStream
};
UploadPartResponse up3Response = client.UploadPart(uploadRequest);

// List parts for current upload
ListPartsRequest listPartRequest = new ListPartsRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId
};
ListPartsResponse listPartResponse = client.ListParts(listPartRequest);
Debug.Assert(listPartResponse.Parts.Count == 3);

// Complete the multipart upload
CompleteMultipartUploadRequest compRequest = new CompleteMultipartUploadRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId,
    PartETags = new List<PartETag>
    {
        new PartETag { ETag = up1Response.ETag, PartNumber = 1 },
        new PartETag { ETag = up2Response.ETag, PartNumber = 2 },
        new PartETag { ETag = up3Response.ETag, PartNumber = 3 }
    }
};
CompleteMultipartUploadResponse compResponse = client.CompleteMultipartUpload(compRequest);

                

Version Information

.NET Framework:
Supported in: 4.5, 4.0, 3.5

See Also